The luminal Ca2+ transient controls Ca2+ release/re-uptake of sarcoplasmicreticulum

Citation
N. Ikemoto et T. Yamamoto, The luminal Ca2+ transient controls Ca2+ release/re-uptake of sarcoplasmicreticulum, BIOC BIOP R, 279(3), 2000, pp. 858-863
Citations number
34
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Biochemistry & Biophysics
Journal title
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
ISSN journal
0006-291X → ACNP
Volume
279
Issue
3
Year of publication
2000
Pages
858 - 863
Database
ISI
SICI code
0006-291X(200012)279:3<858:TLCTCC>2.0.ZU;2-N
Abstract
Our recent study (Saiki, Y., and Ikemoto, N., Biochemistry 38, 3112-3119, 1 999) suggests that Ca2+ release and re-uptake of the released Ca2+ are coor dinated. The following results suggest that the coordination is mediated by the luminal Ca2+ ([Ca2+](lum)) transient, Upon inducing the release of the passively loaded Ca2+ from the SR with polylysine, the luminal Ca2+ ([Ca2](lum)) fist increased then decreased ([Ca2+](lum) transient). The activity of the SR Ca2+ ATPase was monitored at different times after inducing Ca2 release, The phosphoenzyme (EP) formation as determined by the MANT-fluore scence increased concurrently with the initial rapid increase in the [Ca2+] (lum). EP decay (pumping turnover) was accelerated concurrently with a decr ease of the [Ca2+],,. The results suggest that the [Ca2+](lum) transient se rves as a mediator for the acceleration of the Ca2+ re-uptake occurring soo n after the induction of Ca2+ release. (C) 2000 Academic Press.